This invention relates to a chimney flue brush.
Chimneys particularly of wood and other solid fuel burning type necessarily include a chimney flue which allows the escape of the hot combustion gases. As is well known these gases condense on the chimney flue and leave deposits of carbon and creosote which must be regularly removed. The tendency is of course as in any other maintenance operation for this to be overlooked or carried out infrequently with the significant danger of chimney fires and at least the more rapid deterioration of the chimney flue construction.
The brushes which have generally been available to date are of the type including a twisted wire core with the plurality of bristles which extend outwardly to either side of the core and are held in place by being clamped between the twisted wire of the core. The bristles in most cases are of a wire construction which is flexible to some extent but if overflexed will deform thus limiting the amount of compression which can be applied to the brush. The wire bristles of course give a very vigorous brushing action to the inside of the flue and in many cases this brushing action can be too vigorous in that it can scratch the surface for example of a stainless steel flue. This scratching will itself further promote deposits to become attached to the surface and will accelerate the deterioration of the flue. As the bristles are relatively stiff and have a very limited resilience, it is necessary to match fairly closely the size of the brush that is the outside dimension of the brush to the dimension of the flue so the proper scrubbing action is obtained without the danger of the brush becoming stuck. It is also very difficult because of the rigidity of the bristles to reverse the brush. That is, as the brush is being drawn through the flue it tends to form a cone shape and once in the shape it is very difficult to reverse into a cone of the other direction and hence the brush can become jammed within the flue. A yet further problem which arises is that of attempting to get the brush past the damper or other obstructions since its flexibility is very limited. It is also possible for the stiff wire bristles to pull mortar from the flue construction thus again accelerating deterioration.
A further type of construction of chimney brush which is currently available is very similar to that of the metal wire construction described above but in which the metal wire bristles are replaced with synthetic bristles which are thus more flexible. This device alleviates some of the problems which arise with the above metal bristle type but still is generally unsatisfactory. The number of cleanings which are available with a device of this type are also more limited due to the increased likelihood of damage to the bristles.
A yet further device for cleaning chimney flues is of a type including a plurality of flat discs which are mounted upon a central hub with a disc basically being shaped to the inside surface of the flue so that the discs are pulled along the flue and scrape the surface. Devices of this type are of course very rigid in construction and thus difficult or impossible to manoeuvre past deviations in the flue shape or the damper thus limiting the manner in which cleaning can be effected.
Other devices are shown in U.S. Pat. Nos. 2.129.091 (Jacobson), 1,910,358 (Olson), 2,170,997 (Griffin), 1,627,045 (MoGeehin), 3,790,983 (Whitsett) and 1,758,950 (Hunecke). Most of the above show scraper type devices using variously shaped scraper blades mounted on a central hub.